PC powers on, but not starting. Black screen only

kennyga

Honorable
Jan 19, 2014
8
0
10,510
Hello,
I have a problem with my PC. About a week ago I was mining some dogecoins, left the PC running and left my house for a few hours. When I came back the screen was black with no way of getting it back on. I.could only hold power button to switch it off and wasn't ble to get it back on - PSU is definitely fine as it does turn on, fans are spinning and mobo was lighting up. After basic tests of taking out GPU, RAM and putting it back it would still not start. I've tried taking out GPU and using built-in one, switching RAM around and trying single modules (I have 2x 4GB). Still no luck. I tried clearing CMOS multiple times and using all the different combinations of setup, leaving AMD graphics, switching RAM slots etc. So I thought the mobo is dead. I contacted MSI, sent it off and got it replaced. Today I received the new unit (definitely not my old one) and the same thing - pc powers on but nothing on the screen. I've tried connecting it to my TV to make sure it's not the cable or monitor. I even tried leaving just RAM with fans running (no sata cables connected etc) but still no luck. Is it possible that both RAM chips died on me together? Could it be CPU? I did not see anything 'off' when taking the mobo out of the case. Nothing looks damaged or burnt or anything.
My set-up:
MSI Z77A-G45
i5-3750K
AMD R270x
2x4GB Corsair Vengeance LP
OCZ 600w extreme
SSD + HDD

No overclocking on anything. Used to o/c cpu after I bought it but I don't need it overclocked anymore so stays at stock settings.

I did full MSI update before end of April including BIOS and all the drivers (chipset, sound, etc)

I'm out of ideas. I have no access to any other computers, so I can't test RAM or anything


Thanks for any advice
 
Solution
PSUs can sometimes partially fail and partially power up the PC giving you the impression it had to be something else amiss. CPUs almost never go bad and since you replaced the motherboard and tested RAM individually and tested pretty much everything else that leaves the PSU to test next.
PSUs can sometimes partially fail and partially power up the PC giving you the impression it had to be something else amiss. CPUs almost never go bad and since you replaced the motherboard and tested RAM individually and tested pretty much everything else that leaves the PSU to test next.
 
Solution

kennyga

Honorable
Jan 19, 2014
8
0
10,510
I decided to buy a new PSU without checking it with multi-meter first. I had a feeling it would be PSU as I've had it for about 5 years now and I've had a 'problem' with it in the past. Put the new PSU in and everything works fine.

Thanks for your help!